Current sampling and correction system and method applied to electric motorcycles through physical modeling

Abstract

The present invention relates to the field of charging technology, and specifically to a current sampling correction system and method for electric motorcycles through physical modeling, including: obtaining a universal physical model based on the charging circuits of all electric bicycle charging piles to obtain a circuit model library; extracting the target charging PCB circuit board topology, and matching it in the circuit model library to obtain the PCB physical model; obtaining the equivalent resistance parameters of the charging loop based on the PCB physical equivalent model; analyzing the current path of the PCB physical model during charging, designing an interference current compensation algorithm model, and obtaining universal metering parameters; obtaining the charging data of the PCB circuit board during charging through an electric energy metering chip, the charging data including the charging voltage, current and electric energy; and performing equivalent resistance parameter correction and universal metering parameter correction on the charging data. Therefore, the control board model with the same PCB topology structure has universality, and the charging is guaranteed to be reasonable and fair.

Description

Technical Field

[0001] The present invention relates to the field of charging technology, and in particular to a current sampling and correction system and method applied to an electric motorcycle through physical modeling. Background Art

[0002] In recent years, electric bicycles have become an important means of transportation for people to travel short distances. my country is a major producer and consumer of electric bicycles. By the end of 2023, the social stock has reached 350 million.

[0003] As the number of electric bicycles increases, the number of fire accidents related to them is also increasing.

[0004] In response to the frequent fire accidents caused by electric bicycles entering elevators, homes and other enclosed spaces for charging, various regions have successively issued relevant regulations to guide electric bicycles to be charged outdoors in a centralized manner. In a short period of time, the construction of outdoor charging equipment and stations for electric bicycles has developed rapidly.

[0005] At present, the charging and recharging modes of electric bicycles are all profit-oriented, with electricity and service fees charged by operators. The charging mode is often charged based on the maximum charging power combined with a timer. The production and manufacturing costs of the charging pile hardware itself are particularly sensitive. When designing a charging control board based on a low-cost double-sided PCB and high-voltage and high-current charging current sampling and billing, especially in applications where there are many electric bicycle models, the standards of existing vehicles are different, and charging behavior can only be determined by charging current, it brings great confusion to designers, or a series of problems caused by rising costs, electric shock safety, and abnormal charging status determination due to inaccurate current sampling. Summary of the invention

[0006] The purpose of the present invention is to provide a current sampling and correction system and method for electric motorcycles through physical modeling, so as to enable more accurate billing, making the charges reasonable and fair.

[0007] To achieve the above object, the present invention provides a current sampling correction method applied to electric bicycles through physical modeling, including obtaining a general physical model based on the charging circuits of all electric bicycle charging piles to obtain a circuit model library;

[0008] Extract the target charging PCB circuit board topology and match it in the circuit model library to obtain the PCB physical model;

[0009] Obtain the equivalent resistance parameters of the charging circuit based on the PCB physical equivalent model;

[0010] Analyze the current path of the PCB physical model during charging, design the interference current compensation algorithm model, and obtain the general measurement parameters;

[0011] Acquire charging data of the PCB circuit board during charging through the electric energy metering chip, wherein the charging data includes charging voltage, current and electric energy;

[0012] The charging data is corrected for equivalent resistance parameters and universal metering parameters.

[0013] The specific steps of obtaining a universal physical model based on the charging circuits of all electric bicycle charging piles and obtaining a circuit model library include:

[0014] Get the charging circuit diagram of the electric bicycle charging pile;

[0015] Identify the charging circuit in the charging circuit diagram;

[0016] Obtaining specific component parameters of each component in the charging circuit;

[0017] Establish circuit model according to schematic diagram and component parameters;

[0018] The circuit models that have been verified to be effective are sorted and classified to obtain a circuit model library.

[0019] The specific steps of extracting the target charging PCB circuit board topology and matching it in the circuit model library to obtain the PCB physical model include:

[0020] Open the EDA software and import the target charging PCB circuit board file;

[0021] Use software functions to identify and extract network, component layout and routing information on PCB to form the logical and physical topology of the circuit;

[0022] Identify functional circuit modules based on circuit functions;

[0023] According to the functional circuit module, the matching physical model is searched in the established circuit model library.

[0024] The specific steps of obtaining the equivalent resistance parameters of the charging circuit based on the PCB physical equivalent model include:

[0025] Obtaining line parameters of the flow circuit;

[0026] Calculate the corresponding equivalent resistance based on the line parameters;

[0027] Calculate the load resistance based on all equivalent resistances.

[0028] The current sampling and correction system and method for electric motorcycles through physical modeling of the present invention include: obtaining a universal physical model based on the charging circuits of all electric bicycle charging piles to obtain a circuit model library; extracting the target charging PCB circuit board topology and matching it in the circuit model library to obtain a PCB physical model; obtaining the equivalent resistance parameters of the charging loop based on the PCB physical equivalent model; analyzing the current path of the PCB physical model during charging, designing an interference current compensation algorithm model, and obtaining universal metering parameters; obtaining the charging data of the PCB circuit board during charging through an electric energy metering chip, wherein the charging data includes charging voltage, current, and electric energy; and performing equivalent resistance parameter correction and universal metering parameter correction on the charging data. Thus, the control board model with the same PCB topology is universal; the PCB production and processing technology has high precision so that the same product has high consistency; avoiding the electric shock safety caused by the vertical bridge metal sheet solution; avoiding the increase in sensitivity costs caused by the non-double-sided multi-layer PCB design, and ensuring reasonable and fair charges. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 It is a flow chart of a current sampling and correction method applied to an electric motorcycle through physical modeling according to the first embodiment of the present invention.

[0031] Figure 2 This is a flow chart of the first embodiment of the present invention for obtaining a general physical model based on the charging circuits of all electric bicycle charging piles to obtain a circuit model library.

[0032] Figure 3 This is a flowchart of the first embodiment of the present invention for extracting the target charging PCB circuit board topology and matching it in the circuit model library to obtain the PCB physical model.

[0033] Figure 4 It is a flow chart of obtaining equivalent resistance parameters of a charging loop based on a PCB physical equivalent model according to the first embodiment of the present invention.

[0034] Figure 5 This is a flow chart of the first embodiment of the present invention for analyzing the current path of a PCB physical model during charging, designing an interference current compensation algorithm model, and obtaining universal metering parameters.

[0035] Figure 6The present invention is a flowchart of the first embodiment of obtaining charging data of a PCB circuit board during charging through an electric energy metering chip, wherein the charging data includes charging voltage, current and electric energy.

[0036] Figure 7 is a partial circuit diagram of a specific example of the first embodiment of the present invention.

[0037] Figure 8 1 is a current detection principle diagram of the first embodiment of the present invention.

[0038] Fig. 9 4 is a reference resistance data diagram of the first embodiment of the present invention.

[0039] Fig.10 4 is a current correction parameter diagram of the first embodiment of the present invention.

[0040] Fig.11 A data graph of the interference current of each channel is read using the ten-channel electric bicycle charging pile motherboard to load a 1000W device on the ninth channel. DETAILED DESCRIPTION

[0041] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0042] First embodiment

[0043] See also Figure 1 to Figure 6 The present invention provides a current sampling and correction method for electric motorcycles through physical modeling, comprising:

[0044] S101 obtains a general physical model based on charging circuits of all electric bicycle charging piles to obtain a circuit model library;

[0045] The specific steps include:

[0046] S201 obtains a charging circuit diagram of an electric bicycle charging pile;

[0047] It is necessary to extensively collect product manuals and technical documents of various electric bicycle charging piles and communicate with manufacturers to obtain the most comprehensive and up-to-date charging circuit diagrams.

[0048] S202 identifies a charging circuit in a charging circuit diagram;

[0049] After obtaining the circuit diagram, identify and mark the circuit parts directly related to charging. This usually includes key components such as power management module, battery charging controller, current and voltage sensing elements, etc. During the identification process, attention should be paid to the design differences of different circuit structures to provide accurate information for subsequent modeling.

[0050] S203: obtaining specific component parameters of each component in the charging circuit;

[0051] For each identified component, such as resistors, capacitors, transistors, integrated circuits, etc., researchers need to record in detail its model, rating, operating characteristics and other specific parameters. This data can be obtained by consulting component manuals, supplier databases or directly extracted from circuit diagrams.

[0052] S204 establishes a circuit model according to the schematic diagram and component parameters;

[0053] Use professional circuit simulation software (such as SPICE, MATLAB / Simulink, etc.) to create a corresponding circuit model in combination with the schematic diagram and the collected component parameters. This process involves the application of circuit theory knowledge, such as Ohm's law, Kirchhoff's law, etc., as well as mathematical descriptions of the behavior of electronic components. Through simulation running, it can be preliminarily verified whether the model can correctly reflect the working state of the actual circuit.

[0054] S205 organizes and classifies the circuit models that have been verified to be effective to obtain a circuit model library.

[0055] All circuit models that have been simulated and verified to accurately reflect the charging characteristics of charging piles will be systematically organized and classified. The classification criteria may include but are not limited to the output power range of the charging pile, the type of charging protocol, the circuit topology, etc. These models will be stored in an easily searchable database or cloud platform to form a comprehensive circuit model library. This model library can serve as an important resource for the future development of new charging piles, optimization of charging algorithms, or fault diagnosis, and promote the continuous advancement and standardization of electric vehicle charging technology.

[0056] S102 extracts the target charging PCB circuit board topology and matches it in the circuit model library to obtain a PCB physical model;

[0057] The specific steps include:

[0058] S301 Open the EDA software and import the target charging PCB circuit board file;

[0059] Choose professional electronic design automation (EDA) software, such as Altium Designer, Cadence Allegro, etc., which have powerful circuit board design and analysis capabilities. The operator needs to import the original design file of the target charging PCB (such as .GBR, .PCBDOC or other formats) into the software to lay the foundation for subsequent analysis and processing.

[0060] S302 uses software functions to identify and extract network, component layout and routing information on the PCB to form the logical and physical topology of the circuit;

[0061] In the EDA software environment, use its built-in analysis tools to fully analyze the PCB design. This step includes identifying all network connections (i.e. signal paths), the specific locations of components and their physical connections (routing, vias, etc.). Through this process, the logical relationship and physical layout of the circuit can be clearly displayed, forming an intuitive circuit topology diagram, laying the foundation for the subsequent functional module division.

[0062] S303 identifies a functional circuit module based on the circuit function;

[0063] Based on the clear circuit topology, the entire PCB design is further divided into several functional circuit modules according to the circuit function and signal flow. These modules may include power management modules, filter circuits, control logic circuits, protection circuits, etc. Identifying and defining these modules is crucial to understanding the overall design intent and optimizing the design.

[0064] S304 searches for a matching physical model in an established circuit model library according to the functional circuit module.

[0065] For each identified functional circuit module, a detailed comparison is performed with the previously constructed circuit model library. The goal is to find a physical model in the model library that is closest or identical to the current module in terms of structure, component configuration, and functional characteristics. This step may require comprehensive consideration of factors such as the model's electrical characteristics, physical size, and cost to ensure that the selected model can effectively represent the behavior of the target PCB module. Once a match is successful, these models can be used as a starting point for further analysis, simulation, or design improvement.

[0066] S103 obtains equivalent resistance parameters of the charging circuit based on the PCB physical equivalent model;

[0067] The specific steps include:

[0068] S401 obtains the line parameters of the flow circuit;

[0069] After completing the construction of the PCB physical equivalent model, the first task is to accurately measure or calculate the electrical parameters of all wires and traces that make up the charging loop. These parameters include but are not limited to the length, cross-sectional area, material (which determines resistivity) of the conductor, and any special coatings or ambient temperature that may affect resistance. In addition, potential resistance-increasing points such as vias and connectors must also be considered. Use professional measurement tools or directly extract this information through circuit design software to ensure data accuracy.

[0070] S402 calculates the corresponding equivalent resistance based on the line parameters;

[0071] Using basic circuit theory, especially Ohm's law (resistance = voltage / current), combined with the line parameters obtained from step S401, calculate the equivalent resistance of each wire or trace. For complex structures, more advanced analysis methods may need to be applied, such as calculating in sections and then summarizing, or using two-dimensional or three-dimensional field solving software to consider more complex electromagnetic effects. The calculation results should cover the resistance values ​​of all critical paths in the charging loop to prepare for the subsequent total resistance evaluation.

[0072] S403 calculates the load resistance based on all equivalent resistances.

[0073] After obtaining the equivalent resistance of each part, they need to be combined according to the actual connection method of the charging circuit to calculate the total equivalent resistance of the entire charging circuit (sometimes also called system impedance). This step may involve the calculation of parallel resistance (total resistance decreases) and the accumulation of series resistance (total resistance increases). The determination of load resistance is particularly critical for evaluating charging efficiency because it directly affects the amount of loss during energy transmission. A lower equivalent resistance means less energy loss, which usually corresponds to higher charging efficiency and faster charging speed.

[0074] Specifically, when the current sampling point designed by the PCB is not inside the sampling resistor pad, the actual resistance of the current sampling resistor should be the sampling resistor plus the resistance of the PCB trace that deviates from the sampling pad to the actual sampling point in the current flow loop. Figure 7 In the example of the first current sampling loop, the actual sampling resistor value is equal to: Rsens1+R_1B1C, where R_1B1C is the equivalent resistance of the sampling point 1C away from the sampling resistor Rsens1 pad 1B. Because the sampling resistor is a high-precision resistor of several to tens of milliohms, the voltage drop generated when a large current flows through the equivalent resistor R_1B1C is enough to affect the accuracy of Rsens.

[0075] Current sampling crosstalk caused by multiple parallel power supply (latter stage interferes with the previous stage): The first sampling interference is analyzed when only the ninth charging channel is turned on. The ten-channel current sampling resistors Rsens of the single-board ten-channel electric bicycle charging pile mainboard used in the present invention are all 20mΩ / ±1% / 1W power, and a single channel supports a maximum of 5A / 1000W electric bicycle charging. When the ninth channel is charging, the main power supply current flows to Figure 7 As shown by the fishbone arrows in the physical topology, the charging current will flow through all the equivalent resistors R_xBxC from the first to the eighth paths. Figure 7 The equivalent electrical circuit model in the figure shows more clearly that the current starts from R_1B1C on the right side of the figure and flows through the second to eighth equivalent resistors in sequence, and finally reaches the ninth current sampling resistor Rsens9 output to form a loop charging. At this time, the first circuit is not turned on Figure 8 The relay does not form a loop, and no current flows through the current detection resistor Rsens1, so no voltage drop occurs. However, the first sampling point is Figure 8 The voltage between points 1A and 1C shown in the loop model diagram, the voltage drop generated when the ninth current flows through the first equivalent resistor R_1B1C will be mistakenly considered as the current flowing through the first path, and the current detected and calculated by mistake is closely related to the ninth current and the value of the first equivalent resistor R_1B1C. The impact of charging the ninth path on the second to eighth paths is the same as the analysis of the first path. The model analysis shows that any level of charging except the first path will have an erroneous current collection effect on all the circuits before it.

[0076] Current sampling crosstalk caused by multiple parallel power supply (front stage interferes with the back stage): Figure 7 The physical topology of the PCB current sampling loop shows that the detection point C of the two sampling resistors adjacent to each phase is located at the front end of the sampling resistor in the current flow direction. For example, the first / second sampling points 1C / 2C are both located at the front end of the sampling resistor current flow direction. When the first circuit is charged, the charging current will form a voltage difference on the equivalent resistance part of the second circuit, and the second current detection circuit will be erroneously superimposed with a detection current that does not belong to it. Figure 7 The equivalent electrical circuit model in the figure shows more clearly that the current flows from point 1C on the right side of the figure through the second equivalent resistor sampling point 2C to the first pad point 1B of the first sampling resistor Rsens1. That is, the local R_2D2C ​​part of the second equivalent resistor R_2B2C will sense the voltage drop generated by the first charging current and will be considered as the charging current of the second. Since the third current sampling point 3C is not within the range of the second current flow, the second charging will not affect the third current sampling. Similarly, the previous charging will only affect the next level of current collection of the even-numbered channels, that is, the first charging interferes with the second, the third charging interferes with the fourth, and so on.

[0077] Design physical parameter model: Based on the above analysis, it can be seen that the current detection during the charging process will be affected by the charging current of the previous and next stages. To calculate the sampling and correction of each error current, it is necessary to calculate Figure 4 / Figure 5 The equivalent resistance of each path in the current-carrying composite conductor is Figure 6 The R_xBxC and R_xDxC of routes 1 to 10 respectively.

[0078] Calculation of resistance of composite conductor carrying current on PCB: The composite current carrying conductor in the main power supply circuit on PCB is actually composed of PCB copper layer, solder paste layer and current increasing brass metal strip in parallel; in the following description, the resistance of PCB copper layer is recorded as Z Cooper , the solder paste layer resistance is recorded as Z Solder , the brass metal resistance is recorded as Z Steel , the resistance after the three are connected in parallel is recorded as Zδ and the calculation formula is: Zδ=1 / (1 / Z Cooper +1 / Z Solder +1 / Z Steel ), all resistance values ​​are in milliohms.

[0079] In the application of the present invention, the PCB copper cladding layer, the solder paste layer, and the flow-increasing brass metal strip are all rectangular in cross section, and the calculation formula of their respective metal conductor resistance Zx is: Zx = ρ*L / (W*H), where ρ is the resistivity parameter of the conductor, unit Ω·mm 2 / m; L is the conductor length, W is the conductor cross-sectional width, and H is the conductor cross-sectional height, all in mm. According to the table, the PCB copper resistivity at room temperature is: 0.01724Ω·mm 2 / m; Solder paste resistivity: 0.115Ω·mm 2 / m; the resistivity of brass is: 0.071Ω·mm 2 / m.

[0080] Get the length / width / height parameters of PCB copper coating, solder paste, and brass metal strips:

[0081] Conductor length parameters: such as Figure 7 As shown, the schematic path of the equivalent resistors R_xBxC and R_xDxC is drawn with green wavy lines. The physical length is the horizontal straight-line distance corresponding to the two endpoints of the green wavy line. Its length can be accurately measured with the help of PCB design tools or CAD.

[0082] Conductor cross-sectional width, height / thickness parameters: PCB copper cladding width Figure 7The effective width of the red polygon in the middle is 7.62mm, and its design measurement value is 7.62mm. The height is the copper thickness of the PCB surface layer. In this application, the finished copper thickness of the PCB is 1.4mil, i.e. 0.03556mm. The width of the solder paste layer provided by the PCB window is 5mm, and the thickness of the solder paste after soldering is completed is 0.2mm. The width of the brass flow-increasing metal strip is 4mm, and the thickness is 1mm.

[0083] In summary, taking the first channel as an example, the PCB copper cladding, solder paste, brass metal and the parallel composite resistance Zδ of the three corresponding to the first channel are calculated respectively:

[0084] Measure the equivalent resistance R_1B1C of the first channel, corresponding to the physical length on the PCB: 12.069mm;

[0085] Z Cooper =ρ*L / (W*H)=(0.01724*12.069) / (7.62*0.03556)=0.7678mΩ

[0086] Z Solder =ρ*L / (W*H)=(0.115*12.069) / (5*0.2)=1.3879mΩ

[0087] Z Steel =ρ*L / (W*H)=(0.071*12.069) / (4*1)=0.2142mΩ

[0088] Zδ=1 / (1 / Z Cooper +1 / Z Solder +1 / Z Steel )=1 / (1 / 0.7678+1 / 1.3879+1 / 0.2142)=0.1495m

[0089] Ω

[0090] The calculation method for the second to tenth equivalent resistances R_xBxC and the second, fourth, sixth, eighth, and tenth R_xDxC is the same.

[0091] Based on this, a mathematical model is established and relevant parameters are filled in to automatically calculate the R_xBxC and R_xDxC parameters corresponding to each channel. The corresponding parameters and calculation results of the electric bicycle PCB motherboard used in the present invention are as follows: Fig. 9 shown.

[0092] S104 analyzes the current path of the PCB physical model during charging, designs an interference current compensation algorithm model, and obtains general measurement parameters;

[0093] The specific steps include:

[0094] S501 calculates the model correction current generated by the current circuit charging current on all previous circuits;

[0095] First, circuit simulation software or mathematical models are needed to evaluate the electromagnetic interference effect caused by the large current flowing in a certain circuit on the upstream (previous) circuit when the circuit is charging. This includes calculating the additional "noise" current caused by factors such as electromagnetic coupling, parasitic capacitance or inductance. These calculation results form the basis for correcting the previous circuit model to eliminate measurement errors.

[0096] S502 fills in each original current collected during charging of the ninth circuit, automatically calculates the model correction current of all loops of the previous circuit that interfere with the latter circuit, and adds the first actual current after the model correction;

[0097] In this step, the ninth charging circuit is selected as an example to collect its actual current data during the charging process. Through the algorithm model, these raw data are combined with the correction current calculated in S501 to automatically adjust and calculate the actual (corrected) current values ​​of each circuit in the front stage taking into account the interference effect of the rear stage circuit. In particular, for the first circuit, its first actual current after compensation for interference is determined, which is the first step to achieve accurate measurement.

[0098] S503 calculates the model correction current generated by the current circuit charging current on all subsequent circuits;

[0099] Similar to S501, this time the focus is on the interference effect of the current charging circuit on the downstream (later stage) circuit. By analyzing the changes in the electromagnetic field caused by the current flow, the error current that may be introduced to the later stage circuit is calculated, providing a correction basis for the current measurement of the later stage circuit.

[0100] S504 fills in the first and second original currents collected during the first charging, automatically calculates the model correction current of the previous stage interfering with the next stage, and adds the second actual current after the model correction to obtain a universal metering parameter set.

[0101] The first charging circuit is selected as a case study, and the current data of the second circuit is referred to. The algorithm model is used to calculate the interference effect of the first charging current on the second and subsequent circuits, and the actual current reading of the second circuit is adjusted accordingly. The cumulative results of this series of correction processes form a comprehensive universal metering parameter set that is suitable for current measurement of different circuits in a variety of charging scenarios.

[0102] S505 compensates the universal metrology parameter set based on the temperature change.

[0103] Considering the impact of temperature on circuit component performance and current measurement, the universal metering parameter set obtained above needs to be temperature compensated. By analyzing the changes in circuit characteristics at different temperatures and adjusting the metering parameters, the accuracy and consistency of current measurement can be ensured within a wide range of ambient temperatures. This step ensures the robustness of the metering algorithm model and improves the reliability of the charging system under various operating conditions.

[0104] Specifically, error current correction calculation (latter stage interferes with previous stage): Under the premise that the equivalent resistance parameters R_xBxC and R_xDxC of each channel have been obtained, the model correction current Im(x) generated by the current loop charging current for all previous loops is expressed according to Ohm's law I=U / R as follows: the voltage generated by the composite resistance Zδ of the interfered channel divided by the sampling resistance value of the interfered channel, and its expression is:

[0105] Im(x)=(current channel charging current Ic(x)*interfered channel composite resistance Zδ) / interfered channel sampling resistance Zsens

[0106] Figure 7 The equivalent electrical circuit model shows that the actual sampling resistance value Zsens(x) of each channel is the sum of the sampling resistance Rsens(x) and the equivalent resistance R_xBxC, that is, Zsens(x)=Rsens(x)+R_xBxC, R_xBxC is Zδ

[0107] That is: Im(x)=(Ic(x)*Zδ(x)) / (Rsens(x)+Zδ(x)), the sampling resistance Rsens of channels one to ten is 20mΩ

[0108] The ninth channel is connected to 1000W and 2000W loads for charging (the actual currents measured are 4539mA and 8814mA respectively), and the other channels are closed and not charging. The model correction current of the interference caused by the charging current of the ninth channel on the first channel is calculated (see the relevant parameters for details). Fig.10 Physical model automatically calculates the results):

[0109] Charging current 4539mA:Im(1)=(Ic(9)*Zδ(1)) / (Rsens(1)+Zδ(1))

[0110] =(4539*0.149459) / (20+0.149459)=33.668mA

[0111] Charging current 8814mA:Im(1)=(Ic(9)*Zδ(1)) / (Rsens(1)+Zδ(1))

[0112] =(8814*0.149459) / (20+0.149459)=65.378mA

[0113] The calculation method of the model correction current generated by the interference of the ninth path from the second to the eighth paths is the same.

[0114] Data measurement and model verification (1000W charging at the ninth route): The PCB mainboard of the electric bicycle used in the present invention is connected to a 1000W load at the ninth route and starts charging. The original collected current value of each route is printed through the debugging serial port. Fig.11 As shown, the currents are 31mA, 58mA, 31mA, 57mA, 27mA, 55mA, 26mA, 53mA, 4539mA and 14mA respectively; this set of current data clearly shows us the phenomenon of the ninth charging channel for channels one to eight (the rear stage interferes with the front stage) and the ninth channel for the tenth channel (the front stage interferes with the rear stage).

[0115] According to the above-mentioned model correction current calculation method, a mathematical model is established, and the original current of each channel collected during the ninth channel charging is filled in, and the model correction current of all the circuits of the previous stage that interfere with the latter stage is automatically calculated, and the theoretical actual current after the model correction is added, such as Fig.10 The table of "The impact of the back stage on the front stage 1KW" is shown in the figure; the ninth route 2000W charging is the same and will not be repeated here. The original collected current value is referenced Fig.11 , model and actual correction current reference Fig.10 "The power of the rear stage affects the power of the front stage by 2KW."

[0116] Error current correction calculation (previous stage interferes with later stage): The principle and calculation method are the same as those of the later stage interfering with the previous stage. The difference is that the first path interferes with the second path, the third path interferes with the fourth path, the fifth path interferes with the sixth path, the seventh path interferes with the eighth path, and the ninth path interferes with the tenth path.

[0117] Data measurement and model verification (1000W charging on the first route): The electric bicycle PCB mainboard used in the present invention is connected to a 1000W load on the first route and starts charging. The original collected current value of each route is printed through the debugging serial port, and the currents are 4668mA, 26mA, 0mA, 0mA, 0mA, 0mA, 0mA, 0mA, 0mA, and 0mA, respectively; this set of current data clearly shows that the first charging route has interference and only interferes with the second route (the front stage interferes with the rear stage).

[0118] According to the above-mentioned model correction current calculation method, a mathematical model is established, and the original currents of the first and second paths collected during the first path charging are filled in, and the model correction current of the previous stage interfering with the next stage is automatically calculated, and the theoretical actual current after the model correction is added, such as Fig.10The table of "Front stage affects rear stage 1KW" is shown in the figure; the first 2000W charging is the same and will not be repeated here. The model and actual correction current are referenced Fig.10 , the front stage affects the rear stage by 2KW".

[0119] After being processed by the above model and method, the corrected current basically returns to zero. Since the actual current sampling resistance Rsens in the circuit is 20mΩ / ±1% instead of the theoretical value of 20mΩ used in the calculation, it can be calibrated by referring to the electric meter or measuring instrument in actual use.

[0120] S105 obtains charging data of the PCB circuit board during charging through the electric energy metering chip, wherein the charging data includes charging voltage, current and electric energy;

[0121] The specific steps include:

[0122] S601 selects a corresponding electric energy metering chip according to target charging parameters;

[0123] Carefully select the appropriate energy metering chip based on the expected maximum current, voltage range, power accuracy requirements, and target application scenarios (such as home, commercial, or industrial) of the charging system. There are many types of energy metering chips on the market, each with its own advantages, such as high accuracy, wide range, and low power consumption. Comprehensive considerations are required to ensure that the selected chip can meet the performance requirements and cost budget of the entire charging system.

[0124] S602 uses shunt resistors to convert current into voltage signals for measurement by the metering chip;

[0125] In order to enable the energy metering chip to measure current, shunt resistor technology is usually used. This is a simple and effective method, that is, a small resistance is connected in series in the circuit. When current passes through, a small voltage drop will be generated on the resistor, and this voltage is proportional to the current passing through. This weak voltage signal is amplified to the range that the metering chip can detect through a precise amplifier circuit, thereby achieving accurate measurement of current. It is critical to select the appropriate shunt resistor value, which must not only ensure measurement accuracy, but also consider power consumption and heat generation issues.

[0126] S603 periodically reads the voltage, current and electric energy data provided by the electric energy metering chip.

[0127] Through the hardware interface (such as I 2C, SPI or UART) to establish communication with the energy metering chip, write a control program or use the supporting driver software, set the timing or event trigger mechanism, and periodically read the real-time voltage, current value and accumulated energy consumption data from the metering chip. These data are not only the basis for evaluating charging efficiency and monitoring battery health status, but also an important basis for optimizing charging strategies and preventing safety issues such as overcharging and overheating. The collected data should be verified and processed as necessary to ensure the accuracy and integrity of the data, and then it can be stored locally or uploaded to the cloud server for further analysis and remote monitoring.

[0128] S106 performs equivalent resistance parameter correction and universal metering parameter correction on the charging data.

[0129] The collected data can be corrected better through the above method, thereby improving the accuracy.

[0130] Third embodiment

[0131] The present invention also provides a current sampling and correction system for electric motorcycles through physical modeling, comprising: a model library generation unit, a matching unit, an equivalent resistance calculation unit, a universal metering parameter calculation unit, a charging data acquisition unit and a correction unit; the model library generation unit is used to acquire a universal physical model based on the charging circuits of all electric bicycle charging piles to obtain a circuit model library; the matching unit is used to extract the target charging PCB circuit board topology and match it in the circuit model library to obtain the PCB physical model; the equivalent resistance calculation unit is used to acquire the equivalent resistance parameters of the charging loop based on the PCB physical equivalent model; the universal metering parameter calculation unit is used to analyze the current path of the PCB physical model during charging, design an interference current compensation algorithm model, and obtain universal metering parameters; the charging data acquisition unit is used to acquire the charging data of the PCB circuit board during charging through an electric energy metering chip, and the charging data includes charging voltage, current and electric energy; the correction unit is used to perform equivalent resistance parameter correction and universal metering parameter correction on the charging data.

[0132] In this embodiment, an in-depth study is conducted based on the charging circuit of a wide range of electric bicycle charging piles, and a general physical model of the charging circuit is obtained through theoretical analysis, experimental data and simulation technology. These models not only cover basic circuit components, such as power modules, control modules, protection modules, etc., but also incorporate the common characteristics of different charging pile designs. These models are summarized and organized to form a circuit model library, which provides rich reference resources for subsequent personalized design and optimization. For a specific target charging PCB circuit board, a matching physical model is selected from the circuit model library. Through detailed circuit board layout analysis, its topology is extracted, including key charging circuits, control circuits, etc., and the closest design case is found in the model library for matching. If necessary, the model is adjusted and optimized to ensure that it is highly consistent with the physical properties of the target PCB circuit board to form an accurate PCB physical model. Based on the above-mentioned PCB physical equivalent model, the electrical characteristics of the charging circuit are deeply analyzed, especially the equivalent resistance parameters. This includes calculating the wire resistance, contact resistance, PCB trace resistance and internal resistance of the components on the circuit board, which directly affect the current transmission efficiency and energy loss. Through accurate parameter extraction, basic data is provided for subsequent correction algorithms. Carefully analyze the potential interference sources in the current path during charging, such as electromagnetic interference, resistance changes caused by temperature changes, etc., and design an advanced interference current compensation algorithm model. The algorithm aims to monitor and correct the measurement errors caused by these interference factors in real time, and predict and compensate the current measurement value through mathematical models, thereby improving the accuracy of measurement. In addition, combined with common measurement parameters such as charging efficiency and total charge capacity, the universality and practicality of the algorithm are ensured. Using a high-performance power metering chip, the charging voltage, current and power data of the PCB circuit board during the charging process are captured in real time. These data are then sent to a pre-designed correction algorithm. First, a preliminary correction is performed through the equivalent resistance parameters to eliminate the measurement deviation caused by the hardware; then, a secondary correction is performed based on the common measurement parameters to further improve the measurement accuracy and ensure the reliability of the final data.

[0133] What is disclosed above is only a preferred embodiment of the present invention, and it certainly cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A current sampling and correction method for electric motorcycles is applied through physical modeling, characterized in that: include: Obtain a general physical model based on the charging circuits of all electric bicycle charging piles to obtain a circuit model library; Extract the target charging PCB circuit board topology and match it in the circuit model library to obtain the PCB physical model; Obtain the equivalent resistance parameters of the charging circuit based on the PCB physical equivalent model; Analyze the current path of the PCB physical model during charging, design the interference current compensation algorithm model, and obtain the general measurement parameters; Acquire charging data of the PCB circuit board during charging through the electric energy metering chip, wherein the charging data includes charging voltage, current and electric energy; Perform equivalent resistance parameter correction and universal metering parameter correction on charging data; The specific steps of analyzing the current path of the PCB physical model during charging, designing the interference current compensation algorithm model, and obtaining the general measurement parameters include: Calculate the model correction current generated by the current circuit charging current on all previous circuits; Fill in the original current of each channel collected during the ninth channel charging, automatically calculate the model correction current of all loops of the previous stage that interfere with the latter stage, and add the first actual current after the model correction; Calculate the model correction current generated by the current circuit charging current on all subsequent circuits; Fill in the first and second original currents collected when the first charging, automatically calculate the model correction current of the previous stage interfering with the next stage, and add the second actual current after model correction to obtain a universal metering parameter set.

2. The current sampling and correction method for electric motorcycles through physical modeling as claimed in claim 1, characterized in that: The specific steps of acquiring a universal physical model based on the charging circuits of all electric bicycle charging piles and obtaining a circuit model library include: Get the charging circuit diagram of the electric bicycle charging pile; Identify the charging circuit in the charging circuit diagram; Obtaining specific component parameters of each component in the charging circuit; Establish circuit model according to schematic diagram and component parameters; The circuit models that have been verified to be effective are sorted and classified to obtain a circuit model library.

3. The current sampling and correction method for electric motorcycles through physical modeling as claimed in claim 2, characterized in that: The specific steps of extracting the target charging PCB circuit board topology and matching it in the circuit model library to obtain the PCB physical model include: Open the EDA software and import the target charging PCB circuit board file; Use software functions to identify and extract network, component layout and routing information on PCB to form the logical and physical topology of the circuit; Identify functional circuit modules based on circuit functions; According to the functional circuit module, the matching physical model is searched in the established circuit model library.

4. The current sampling and correction method for electric motorcycles through physical modeling as claimed in claim 3, characterized in that: The specific steps of obtaining the equivalent resistance parameters of the charging circuit based on the PCB physical equivalent model include: Obtaining line parameters of the flow circuit; Calculate the corresponding equivalent resistance based on the line parameters; Calculate the load resistance based on all equivalent resistances.

5. The current sampling and correction method for electric motorcycles through physical modeling as claimed in claim 4, characterized in that: The specific steps of analyzing the current path of the PCB physical model during charging, designing an interference current compensation algorithm model, and obtaining the universal metering parameters also include: compensating the universal metering parameter set based on temperature changes.

6. The current sampling and correction method for electric motorcycles through physical modeling as claimed in claim 5, characterized in that: The specific steps of obtaining charging data of the PCB circuit board during charging by using the electric energy metering chip, wherein the charging data includes charging voltage, current and electric energy, include: Select the corresponding energy metering chip according to the target charging parameters; A shunt resistor is used to convert the current into a voltage signal for measurement by the metering chip; Regularly read the voltage, current and power data provided by the power metering chip.

7. A current sampling and correction system applied to an electric motorcycle through physical modeling, applied to the current sampling and correction method applied to an electric motorcycle through physical modeling as claimed in claim 1, characterized in that: include: Model library generation unit, matching unit, equivalent resistance calculation unit, universal metering parameter calculation unit, charging data acquisition unit and correction unit; The model library generation unit is used to obtain a general physical model based on the charging circuits of all electric bicycle charging piles to obtain a circuit model library; The matching unit is used to extract the target charging PCB circuit board topology and match it in the circuit model library to obtain the PCB physical model; The equivalent resistance calculation unit is used to obtain the equivalent resistance parameter of the charging circuit based on the PCB physical equivalent model; The universal metering parameter calculation unit is used to analyze the current path of the PCB physical model during charging, design an interference current compensation algorithm model, and obtain universal metering parameters; The charging data acquisition unit is used to acquire charging data of the PCB circuit board during charging through the electric energy metering chip, and the charging data includes charging voltage, current and electric energy; The correction unit is used to perform equivalent resistance parameter correction and universal metering parameter correction on the charging data.

Images